``````Duke Participation in SAFOD: Two Collaborative Seismic Profiling Studies using the Geophone Array in the SAFOD Pilot Hole

“我们建议使用SAFOD试验孔中的地震检波器阵列对圣安德烈亚斯断裂带进行随钻地震(SWD)研究。这项研究将井下部件添加到目前由SAFOD现场资助的地面地震剖面和钻井项目中。社署研究的科学目标是：(1)确定SAFOD场地的亚垂直断层结构和材料性质；(2)开始对这些结构和性质进行时间推移监测。在我们研究的野外部分，我们将使用Pilot Hole地震检波器收集数据。这项研究的目的是确定圣安德烈亚斯断层附近和内部的地下岩石性质，并监测它们随时间的变化。特别是，我们正在寻求确定SAF微震震源区周围材料的整体性质。我们将检查我们收集的所有SWD数据的波传播效应，如各向异性、衰减和复杂的反射和折射效应。通过利用试验孔地震检波器阵列在地震中安静的井下环境，我们还将为未来对SAFZ进行“延时”地球物理监测建立一个高分辨率基线数据集。这些数据被用来跟踪能量储集层的岩石-流体-应力演化，我们希望最终将这一程序应用于SAFOD现场。

`We propose a seismic-while-drilling (SWD) study of the San Andreas Fault Zone using the geophone array in SAFOD Pilot Hole. The study adds the downhole components to the currently-funded surface-seismic profiling and drilling projects at the SAFOD site. The scientific objectives of the SWD study are to: (1) establish the subvertical fault structure and material properties of the SAFOD site and (2) begin the time-lapse monitoring of these structures and properties. In the field portion of our study, we will collect data with the Pilot Hole geophones. The purpose of this study is to determine the subsurface rock properties adjacent to and within the San Andreas Fault and in monitor their time dependent changes. In particular we are seeking to determine the bulk properties of the materials surrounding the source zones of SAF microearthquakes. We will examine all the SWD data we collect for wave propagation effects such as anisotropy, attenuation, and complex reflection and refraction effects. By utilizing the seismically quiet downhole environment of the Pilot Hole geophone array, we will also be establishing a high-resolution baseline data set for future "time-lapse" geophysical monitoring of the SAFZ. Such data are used to follow the rock-fluid-stress evolution of energy reservoirs, a procedure we wish to eventually apply at the SAFOD site.